Industrial refrigerators for storage of vegetables. Refrigerated warehouses for fruits and vegetables Industrial fridge for storage of vegetables

Vadim Greenberg

For people who are far from understanding of modern storage technologies, familiar with childhood, the concept of "vegetable store" can cause not too pleasant visual and olfactory associations. However, those who are "in the topic", a gigantic technological jump, which occurred in this area in the last 20-30 years. A modern warehouse for storing vegetables and fruits is equipped with a whole complex of engineering systems that allow you to turn simple, at first glance, the task of the most long-term harvest in a high-tech managed process.

To assess the complexity of this process, you need to at least briefly focus on what, in fact, the tasks have to be solved in the storage process - with what natural processes that occur with the fruits and vegetable products covered in the cold winter time have to fight.

In plant products, which include vegetables and fruits, is contained from 75 to 95% water. From the moment of harvesting in fruits and vegetables, chemical and microbiological processes begin to occur, the character of which is determined by biological functions. The main physiological process that continues in fruits and vegetables after collecting is breathing. The intensity of respiration and the associated exchange processes depends on temperature. In particular, for fruits and berries is characterized by the so-called post-harvest maturation, during which, by the transition of nutrients from the pulp, seeds are formed. It is accompanied by a decrease in chlorophyll (gradually disappears green) and the appearance of other pigments, the accumulation of ethylene, the content of vitamins and moisture decreases. Thus, the possible shelf life of vegetables and fruits is determined mainly by their maturity when harvesting.

In practice, two degrees of maturity - removable and consumer. Removable maturity is determined by the need for subsequent transportation and storage capabilities, and consumer-fitness for use. From the point of view of the consumer, one of the main processes occurring in fruits and vegetables after collecting is the evaporation of moisture. Evaporation leads to a decrease in mass and fading. The noticeable fiction of fruits occurs with a loss of 4-6% moisture, and berries and leafy vegetables - with a loss of 1.5-2%.

Consequently, the main task when storing is reduced to the braking of physiological biochemical processes, preventing the development of phytopathogenic microorganisms and reduce moisture loss. One of the effective ways to achieve this result is a rapid pre-cooling. The speed of such cooling depends on the type of fruits and vegetables. If removable and consumer maturity coincide, which is characteristic of berries (including cherries, cherries) and cucumbers, or occurs through a relatively short period, like apricots, peaches, drain and melons, the cooling process should take no more than 5 hours. And, for example, in winter varieties of apples and pears, which reach consumer maturity in the process of long-term storage, the cooling process can occupy a day.

That is, the first task that needs to be solved, regardless of whether vegetables and fruits are laid for storage in close proximity to the collection place are either transported to the place of storage at considerable distances, is to ensure the possibility of pre-cooling. It can be carried out in conventional storage chambers at a frequency of air exchange 30-40 times per hour, in special chambers of pre-cooling with an increased air exchange frequency, in the intensive air cooling machines, including tunnel type, as well as cold water Irrigation or immersion method.

The solution to the problem is sufficiently long-term storage of vegetables and fruits, thus, can develop two main ways: storage in close proximity to harvest and storage in the consumption region. Regions of the most concentrated consumption are metropolis, where the cost of storage is large enough due to high rental rates of warehouse space. Nevertheless, this option may well be considered for imported fruits and vegetables purchased by large, including ship, parties.

However, the most interesting from a commercial point of view is the option of the territorial association of the process of growing, harvesting and subsequent storage. In this case, warehouses for storing vegetables and fruits can be erected at one of the relatively inexpensive construction technologies, in particular, using lightweight metal structures or for frameless technology. Frame storages are made of quick-scale lightweight metal structures. To create a heat-insulating circuit, a sandwich panels are used, a profiled steel sheet is used for the outer sheaving. This design is relatively easily scaled, which allows you to increase storage.

The use of frameless construction technologies allows you to speed up the storage facilitation process through the use of panel-forming machines. Created as a result of the use of such technology of structures have high strength, resistant to wind and snow loads. Their essential advantage is also the absence of a powerful foundation. The warehouses are erected by the frameless method can be single or two-layer, with a layer of insulation between layers.

In the future, in accordance with the task, options of varying degrees of technological equipment can be selected. This is determined by the type of stored products - a homogeneous or in the assortment, the method of its storage - in bulk or in the packaging container, an estimated shelf life. Accordingly, with long-term storage of diversified products it is necessary to ensure temperature zoning.

The most practical option for storing vegetables and fruits using a refrigeration system and ventilation system. Its problematics considered in detail in a large number of publications relating to the construction and equipping of medium-temperature refrigeration warehouses. At the same time, special technical devices are very important, which are the warehouses for storing vegetables and fruits that are equipped, primarily equipped with an adjustable microclimate system and a controlled atmosphere. The organization of an adjustable atmosphere is a technology that allows you to significantly increase product storage duration and maintain its quality. Storage of fruits and vegetables under an adjustable gas environment occurs in special vegetable stores, refrigeration chambers, polymer films, polyethylene containers.

In this area there are also several levels of complexity. At the first level, the controlled carbon dioxide content is mainly achieved when maintaining the necessary temperature regime and air humidity. In this case, the parameters of the controlled atmosphere approximately correspond to the oxygen content of 3-4% and carbon dioxide of 3-5%, though the oxygen content in a conventional atmosphere is about 21%, nitrogen - 78%, carbon dioxide 0.03%. The excess of CO2 content leads to a fairly fast spider of vegetables and fruits, while, in particular, there may be an unpleasant taste and smell, the development of some fungal formations is observed, the transport of the preserved vegetables and fruits is worse. The problem of absorption of excess carbon dioxide is solved by the use of scrubers (sometimes called gas places). Using scrubber from refrigerators, carbon dioxide and part of the generated ethylene are removed. The removal method is quite simple and based on the use of activated carbon, which adsorbs the gas molecules. The air from the refrigerator is pumped through activated carbon using a low pressure fan that consumes the minimum of electricity, and then returns back.

A more complex system of creating a controlled atmosphere provides for a decrease in the oxygen content of up to 2-5% and carbon dioxide to 1-3%. This is achieved by displacing them with nitrogen, for which the generator is integrated into the system, which produces it from the surrounding air. A nitrogen generator consists of two interchangeable tanks with carbon molecular sieves, which can adsorb oxygen molecules throughout a certain time. When one of the tanks saturates, automatic switching to another tank occurs. In the filled tank at this time, the regeneration process is carried out.

The third, highest in terms of technological implementation, the level of creation of an adjustable atmosphere provides not only an ultra-low oxygen concentration (in the range of 1-1.5%) and carbon dioxide (0-2%), but also a decrease in the content of fruits released during ripening process and Ethylene vegetables. This scheme requires the use of another class of devices - catalytic ethylene converter. Gas ethylene is allocated by vegetables and fruits and stimulates their maturation, so control over its content makes it possible to store them over a long period of time.

The market contains catalytic ethylene converters from many manufacturers. The general principle of their action is based on forced air recycling over the catalyst layer, stored at elevated temperature. In the process of catalytic interaction of ethylene with air oxygen, it is disintegration of carbon dioxide and water.

With the help of the converter, the ethylene ratio to the total air volume in the 1/109 chamber without the use of toxic chemical reagents is possible. Thus, the process of cleansing air in refrigeration chambers does not have a negative impact on the environment. No less important is the small amount of energy required for the operation of the converter. This is ensured by heat recovery in the closed system of the converter and the refrigeration chamber.

However, the process itself is generally stored, as a rule, does not end. It is also necessary to provide technical stage of imparting to vegetables and fruits of commodity qualities, that is, to organize the process of dosing directly before sending products to the outlets. Consider this process on the example of such a well-known fruit as a banana. These fruits grow in the tropics and subtropics, while industrially grown mainly in South and Central America. Bananas are assembled in a misappropriate form, and on the way and upon arrival in consumption items, they rose in warehouses. The bananas are shipped to Russia with powerful refrigerator vessels whose refrigeration units allow you to preserve fruits in a state of "removable" maturity during the entire transport period. The shelf life may vary from 28 days from the moment of collecting up to 40-50 days. Its increase is achieved through the use of an adjustable atmosphere when stored.

When preparing for retail trade, the product is communicated to a certain degree of maturity due to the maintenance of it in the gap chambers. The ripening process is stimulated by ethylene (as opposed to storage stage, when ethylene content, on the contrary, decreases). Ethylene processing is performed once.

The process of bringing the misappropriate fruits in storage facilities, warehouses or specially equipped cameras to the state of consumer ripeness is called dose. Removal mode can be accelerated (up to 4 days), normal (5-6 days) and slow (8 days). Higher fruit quality is observed with slow dialing of bananas at reduced temperatures. In the summer and winter, the dosing temperature range differs. If in the process of dosing weight to allow supercooling, in the green banans there are longitudinal bodies of brown under the top layer of the peel, the peel becomes gray. The result of increasing the temperature beyond the optimal interval is the softening of the pulp, the weak legs of the fruit, bursting the peel and brown spots on the greenish-yellow peel. The subsequent storage period is also significantly reduced.

In the dosing chamber, it is necessary to maintain a high level of humidity - 85-95% to maintain the product and prevent the loss of moisture with vegetables and fruit. In the course of this process, both the air temperature in the chamber and the temperature of the pulp of the fetus are controlled (since the fruits are highlighted in the process of ripening the fruits). The ambient temperature is optimal for the dosing process: +15 ... + 18 ° C.

Conducting the above, it can be noted that in the technological scheme of a modern high-tech complex for long-term storage of vegetables and fruits, an accelerated pre-cooling stage should be provided (before booking for storage or before transporting to the place of storage). In a multidiscipline (for storing various types of vegetables and fruits), storage chambers with automatic temperature control in the range from -2 to +7 ° С with a system of maintaining the necessary level of air humidity system should be provided.

If storage is carried out under conditions of a controlled atmosphere, the repository, along with the necessary complex of refrigeration and ventilation equipment, can be equipped with scrubber, nitrogen generators and ethylene converters. The final stage is important - the acquisition of commodity and translating products from the cooled state in which they were stored, to a state corresponding to the terms of sale. At the same time, condensate should not be formed on the products. This operation is performed in the so-called "sep drop chambers". In addition, at this stage, the process of ripening fruits and vegetables can be implemented, for which the storage is equipped with dosing chambers.

All processes considered by us require not only expensive equipment, but also accurate compliance with all parameters. So, before enjoying the taste and aroma just bought the "winter" apple, it will not hurt to remember that his appearance on our table was preceded by a complex, very technological and such an important process of maintaining a commodity and consumer properties.

Requirements and selection of equipment

A. Rikoshinsky

The offer on the Russian market of services of refrigerator warehouses is far behind the growing demand. Most likely, and in the foreseeable future, this trend will continue - the needs for storing the cargo at low temperatures will continue to grow, which is associated with the expansion of internal consumption, which is the growth of both the own production of frozen products and their imports.

The modern refrigerator warehouse is, as a rule, a separate building in which storage chambers and auxiliary rooms are located. Warehouses have access to automobile and railway tracks and are equipped with indoor or open overpass for receiving and vacating products. Constructive warehouse solutions must match SNiP 2.11.02-87 "Refrigerators", according to which heat supply, heating, ventilation, water supply and sewage must meet the following requirements.

Cleaning the air removed from the indoor and hardware compartments of ammonia refrigeration plants is provided in accordance with the requirements of SNiP 2.04.05-91.

Emergency ventilation should have launchers and ventilated premises (at outputs), and out of them (in outer doors), as well as automatically turn on with an increase in the concentration of ammonia in rooms above the maximum permissible.

Estimated air temperature and ambulance air exchange

Room	Calculated air temperature, ° С	Multiplicity of air exchange
		Influx	Hood	Emergency exhaust
Machine and hardware compartment of refrigeration units: ammonia freonov		By calculation, but not less than 2 By calculation, but not less than 3	According to SNiP 2.04.05486. Also
Refrigerated distribution device for ammonia refrigeration units (in separate rooms with lobby for multi-storey refrigerators, on antlesol in single-storey refrigerators)	5	–	At least 3 (periodic)	–
Staircase	5	–	–	–
Machine branch of elevatov	5	–	–	–
Charged battery package	16	By calculation Plus Natural extract according to PUE
Electrolyte	16	By calculation		–
Repair room of self-propelled machines	16	2	2	–
Chargers room	5	By calculation	–

Fans and electric motors for exhaust and emergency ventilation of ammonia machine and hardware compounds are provided in explosion-proof execution.

Premises for storing potatoes, vegetables, fruits must be equipped with devices and devices that allow you to control and automatically maintain air temperature, as well as relative humidity control devices. The condensation of moisture on the inner surfaces of the walls and the ceilings is not allowed.

Refrigerators must be equipped with drinking, industrial and fireproof waterways and sewage systems.

Internal fireproof water supply in the cooled part of the refrigerator buildings (refrigeration chambers with transport corridor) is not provided. Estimated water consumption for outdoor fire extinguishing should be taken as for buildings.

In the buildings of refrigerators, an open laying of internal industrial water supply networks should be provided. The gasket of water supply networks in cooled rooms is not allowed.

To cool the machines and devices of refrigeration units, water quality water is allowed with the following main indicators:

• rigidity total - 2 ... 6 mg-eq / l;
• the presence of free carbon dioxide is 10 ... 100 mg-eq / l;
• the concentration of hydrogen ions pH \u003d 6.5 ... 8;
• turbidity - 2 ... 5 mg / l; Iron - 0.1 ... 0.3 mg / l.

Water consumed for washing equipment, equipment and floors, salted fishing cameras, electrolyte at charging stations and repair premises of self-propelled machines, should meet the requirements of GOST R 51232-98.

The norms of water consumption and drainage and water temperature

Manufacturing process	unit of measurement	Water pipes		Sewerage
		Water consumption rate, l	Water temperature, ° С	The norm of drainage, l
Towing air coolers in cameras: with positive temperatures with negative temperatures	m 2 surfaces m 2 surfaces	10 –	At least 15. –	15 3
Cooling capacitors and compressors	Aggregate on passport data
Washing: floors lifting and vehicles (electric loaders, electric cars) inventory	m 2. 1 car m 2 surfaces	3 150	Up to 50 Up to 50 At least 60.	3 150

Note. The time of thawing air coolers - 0.5 h.

Watering cranes must be installed in salted fishing rooms, electrolyte at charging stations and in repair rooms of self-propelled machines at the rate of one crane for 500 m 2 floors of the floor, but at least two cranes for the floor, on cargo platforms - every 25 m. In the chambers Salted fishing and on cargo platforms should be provided by a dry tube water supply.

For refrigeration units should be provided, as a rule, revolving water supply systems.

Water that is formed when the air coolers is thawing are usually used in a circulating water supply system or other technological needs.

Household and industrial wastewater should be discharged into household sewage sewage.

Wastewater from devices and devices should be removed into household sewers through individual or group hydraulic shutters located in heated rooms.

The sewage networks deployed in rooms with negative air temperatures and in unheated rooms must be equipped with a heating system.

Wastewater from washing platforms must be removed into household sewers. On issues should install wells with hydraulic.

The efficiency of any warehouse, especially when it comes to storing food, depends on the complex of factors - the range of stored products, the location of the warehouse, the qualifications of employees, etc. Not the last place is given to the level of warehouse equipment and automation of business processes. The rapid development of the wholesale and retail trade in food, the consolidation of trading facilities, the development of large retail chains, etc. - All these reasons determine the increase in attention to the quality of warehouse equipment. If not every individual product, then a group of goods included in the assortment set requires specific conditions and storage technologies. Considering the fact that, depending on the size of the range of a modern food warehouse, it can be up to 50 thousand items, the task of providing the warehouse with the necessary equipment is quite complex. For this reason, the choice of effective refrigeration equipment should be preceded by a comprehensive study of the technical and economic conditions of the process of processing material flows. Only on the basis of careful analysis and calculations can be successfully solved by technical issues arising from the selection of equipment and its installation.

To remove heat from refrigeration chambers, three main types of cooling systems are used:

• direct cooling;
• with an intermediate coolant;
• air (these cooling systems are rarely used).

The main characteristics that are taken into account at the first stage when choosing refrigeration equipment include:

• the temperature range provided (supported temperature modes);
• ease of installation and service;
• technical reservation coefficient;
• refrigerant costs;
• the degree of factory readiness of equipment, etc.

The following tasks are then solved:

• choose a cooling scheme;
• determine the type of refrigerant;
• determine the optimal performance of the compressor, condenser and evaporative parts of the system at various loads;
• select the optimal scheme of pipeline laying.

Naturally, in each particular case there is a large number of private technical tasks, the reliability of the entire system depends on the correctness of the solution.

To maintain the required temperature mode, they are used, as a rule, the system of direct cooling or system with a coolant. In the direct cooling system, the liquid refrigerant from the capacitor, passing the control valve, enters the evaporative batteries located in cooled rooms. Due to the heat of ambient air, the refrigerant boils, cooling the air. Couples of refrigerant of batteries are sucked by a compressor. The direct cooling system necessarily includes a compressor unit and one or more air coolers placed in storage chambers. In addition, depending on how the liquid refrigerant is supplied to the evaporative batteries, direct cooling systems are divided into pumping and non-visible. In non-visible systems, the liquid enters the battery under the action of the pressure of condensation condensation and the refrigerant boiling, and in the pumping it is supplied by a special pump. Pump systems are used mainly on large refrigerators.

As a cooling medium, refrigerant (freon or ammonia) is used as a coolant (freon or ammonia), which, when boiling in the air cooler, takes heat from the environment. When choosing between freon and ammonia, the following considerations take into account: The advantages of use as an ammonia refrigerant (R717) are due to the fact that it has thermodynamic and thermophysical characteristics, allowing to obtain high kp. In refrigeration plants, chemically neutral with respect to most design materials of refrigeration plants is not dissolved in lubricating oils used in the designs of refrigeration plants, with the exception of copper and alloys based on it, not sensitive to moisture and easily detected in the event of a leakage, does not contribute to the creation The greenhouse effect has a low cost (no more than 2,200 rubles / t) and easily available on the market.

At the same time, ammonia has a number of serious flaws. In particular, this substance is highly toxic (it is believed that the maximum permissible concentration of ammonia in the work premises should be no higher than 20 mg / m 3, but even at a lower concentration, the characteristic smell of ammonia in the event of its appearance causes a strong panic; at higher concentrations, serious concentrations appear Difficulty of breathing up to choking; the deadly concentration of ammonia is 30 g / m 3), it is explosive (at a concentration in air 200 ... 300 g / m 3 arises the threat of spontaneous explosion; the temperature of self-ignition is 650 ° C), it creates hazard of burns when dissolved in Water, since this process is accompanied by the release of a significant amount of heat, and in addition, has a high discharge temperature in compression in refrigeration compressors.

These flaws of ammonia lead to the emergence of serious organizational and technical and legal problems in designing, installation and operation of ammonia refrigeration. In this regard, in the last 10 ... 15 years, when solving the question of choosing a refrigerant agent, preference is increasingly given to halogen-containing hydrocarbons - chladones, or, as they are called in everyday life, freon. Of these, the most widely used reference (freon) R22. This refrigerant is non-toxic and explosion-proof, it has a low discharge temperature in compression in compressors, good (compared to other chladones) Thermophysical and thermodynamic characteristics, it is chemically neutral to most structural materials, has a rather low ozone-sorrising potential (ORP \u003d 0.05; This indicator is close to ammonia), in large quantities, it is produced in Russia, and its cost is acceptable.

The advantages of the direct cooling system include: simplicity of refrigeration design; Fast cooling of the chambers, which begins immediately after the start of the compressor; The possibility of using higher boiling temperatures to maintain the required temperatures in the cooled volume compared to other methods of cooling, which makes the system of direct cooling in operation of the most profitable, especially for low-temperature chambers (freezers). The disadvantages of the direct cooling system are: the risk of penetration into refrigerant cooled rooms, such as ammonia, smell and the concentration of which can adversely affect the quality of the cooled product and the health of people operating equipment; Increased fire hazard (when working with combustible refrigerants); The difficulty of regulating the compressor operation, especially with multiple chambers with different temperatures.

In installations with indirect (intermediate) cooling, a liquid cooler is used. A decrease in temperature in refrigeration chambers is achieved by heat exchange between the cooled medium and a cold cooler circulating in heat exchangers. The coolant in turn is cooled in the evaporator at boiling refrigerant. Such a system consists of two refrigeration contours: fluid cooling systems (chiller) operating on the refrigerant, and the contour of the intermediate coolant (water, propylene glycol or formative coolars). The heat of the environment in the air coolers is transmitted by an intermediate coolant, with which it is transferred to the refrigerant.

The advantages of the cooling system with an intermediate coolant are as follows: The ability to penetrate the refrigerant directly into the cooled medium (in the cooled product); Easy to regulate the temperature of the cooled medium in refrigeration chambers, which is achieved by changing the amount of the cooler sent to the heat exchange unit of the cooling chamber. However, compared to the system of direct cooling during cooling with an intermediate coolant, it is required: additional linear components - a heat exchange unit (evaporator), a pump, shut-off fittings; The compressor is greater cooling capacity, since, in the presence of a coolant (intermediate coolant), the refrigerant should boil at a lower temperature, and at the same time decreases both coolness and efficiency of the compressor; Large electricity consumption for cold receipt and transmission.

The direct cooling system may be centralized and decentralized. In a centralized scheme, one multicompressory unit is used as a refrigerating machine, which supplies all air coolers. The decentralized scheme consists of several local refrigeration systems, completely independent of each other. Centralized systems with a multicompressor unit are more convenient to manage than decentralized, since controlling compressors, capacitors and air coolers can be from one place. Also more convenient maintenance and repair of such systems, because the compressor equipment and the aggregates of the decentralized system are placed, as a rule, in different parts of the warehouse, which makes it difficult for their maintenance. In turn, a decentralized cooling system has its advantages:

• a special room for a multicompressor unit is not required, and the installation of small one-compressor installations does not make strict requirements for the area;
• in small single-compressor installations, a high reservation coefficient (repair or replacement of one of them does not have a decisive effect on the performance of the system as a whole);
• the decentralized cooling system involves a small length and a simple pipeline layout system.

As already noted, various liquids can be used as a liquid cooler in installations with indirect cooling. In the temperature range up to +2 ° with the best coolant in thermophysical, economic and environmental parameters is water. Its disadvantages are high corrosion activity in relation to metals and a tendency to deposition of salts on the walls of the equipment. At temperatures from +2 to -20 ° C, the combination of the characteristics of thermophysical, economic, toxicological and organoleptic, tolerance to the change in the conditions of operation, reliability and stability is the best propylene glycol coolant. At temperatures below -20 ° C, the advantages that propylene glycol gives rise to an increase in its viscosity, and formative colakelors are inherent to the fore, which are inherent in extremely attractive thermophysical characteristics, practically not inferior to CaCl 2-based brine and the best than many other colasters. .

However, their sensitivity to air pollution and oxygen made it possible to use formative colasters only in closed systems in a limited temperature range and in compliance with a number of precautions and restrictions.

In conclusion, we note that the construction market of refrigerator warehouses will develop in perspective in two directions: companies that position themselves as wholesale traders offering a large range of equipment, a variety of prices, several suppliers with a wide model side; Companies performing turnkey projects - clarifying customer problems, develop a specific project, choosing the necessary equipment, etc. In any case, the future for those companies that can provide the consumer for reasonable money to solve its tasks and high level of technical support and Service.

On refrigerators for storing fruits and vegetables provide:

• storage chambers with automatic temperature control from -2 to + 7 ° C and relative air humidity 70-95%;
• fruit and vegetables ripening cameras with automatic temperature control from 8 to 20 ° C and relative air humidity 80-90%;
• room processing of fruits and vegetables (bulkheads, packaging and packaging) with automatic temperature control from 12 to 15 ° C without regulation of relative humidity;
• separation chambers with temperatures from -2 to + 20 ° C;
• fumigation chambers (on distribution refrigerators).

Capacity of storage chambers - from 50 to 250 tons or more. Storage chambers must be filled within 7-10 days, which will ensure uniform cooling of all fruits. When loading cameras, refrigeration equipment must be turned on. The containment of fruits and vegetables with a temperature above 8 ° C in the chamber with a capacity of up to 200 T is allowed to 8%, and in the chamber more than 200 tons - 6% of the camera capacity.

The degree of loading of the chamber affects the relative humidity of the air in it. Thus, depending on the degree of loading the chamber in the amount of 100, 50 and 25%, the relative humidity in it will respectively be 86, 78 and 68%. The decrease in the degree of loading affects the deterioration of circulation conditions.

Fruits and vegetables that are most sensitive to insufficient humidity (with a weak water-holding capacity), it is more expedient to store in a smaller capacity chambers located in the middle of the refrigerator circuit and having a smaller surface of the exterior fences.

In the absence of special premises for processing and sorting fruits during the shipment period, it is necessary to select one of the chambers in which the temperature of 2-6 ° C is maintained in the preparation of parties to shipping for distribution refrigerators and 10-12 ° C when shipping into the trading network.

When shipping fruits on distribution refrigerators, an increase in their temperature during the period of bulkhead is allowed only for a short time not higher than 2-4 ° C.

Before shipment to the trading network in the warm season, the temperature of the fruit must be raised gradually within 2-3 days to avoid condensate on them. At the same time, the air temperature is maintained by 2-3 ° C above the temperature of the selected product, the relative humidity is 75-80%.

Some fruits and vegetables (pears, tomatoes, etc.) do not ripe in the storage process, therefore, in a few days before implementing, they are transferred to a premises with enhanced air circulation and hold there for 3-7 days at a temperature of 18-20 ° C and relative Humidity 90%.

Refrigerators for vegetables and fruits

The choice of suitable storage technology ensures the safety of the final product in the initial freshness. Lower storage temperatures provide an increase in shelf life. In the storage of products you can help industrial refrigeration chambers, as well as a shock freeze chamber.

You can find out more about refrigeration equipment on our website.

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Refrigeration equipment for storage of vegetables and fruits.

Kholspeztsstroy company is engaged in the design and construction of industrial chambers for storing vegetables and fruits on new technologies - we try to maximize the shelf life of the "living" product. To preserve the quality and food value of fruits and vegetables, we equip the storage facilities with specialized refrigeration equipment.

Vegetable stores

We can order the construction of vegetable stores, both ready-made solutions and selected individually for your needs using modern high-quality equipment that we will specifically select under you.

During the development process, all factors will be taken into account on the quality of preservation of fresh harvest.

The building of the vegetable store is designed depending on the method of storing products - scattering or in container. Anyone is a complex, responsible process, so you need to trust the work with experienced specialists and our company always performs work efficiently.

When building both fructurassic and vegetable stores, another important factor is taken into account - the creation of a favorable microclimate in the storage process. To do this, it is necessary to provide a system of ventilation and artificial cold, pick up refrigeration equipment with a microclimate control function.

Fruptustustoral

In the fruit store, which we plan, you can store apples up to 12 months, pears up to 8 months, grapes until six months. Our objects can rightfully be called the last word of science and technology in the area of \u200b\u200bstorage of fruits and vegetables. Products passes through the conveyor, sorted in size, quality and cleaned.

3 types of adjustable atmosphere (gas environment) are isolated:

1. Adjustable traditional atmosphere (TRADITIONAL CONTROLLED ATMOSPHERE) - Oxygen content 3-4%, and CO2 - 3-5%.
2. Low oxygen content LO (Low Oxygen) - 2-2.5% oxygen and 1-3% CO2.
3. Ultra low oxygen content ULTRA Low Oxygen (ULO). The content of O2 in the chamber is less than 1-1.5%, the content of carbon dioxide is 0-2%.

We have various technologies for storing vegetables and fruits in an adjustable gas environment:

The technology of rapid decrease in oxygen concentration is called RCA (RAPID CONTROLLED ATMOSPHERE) - when loading the chamber, the concentration of O2 decreases to 2.5-3% in 1-3 days. The so-called ultrafast decrease in the level of ilos oxygen (Initial Low Oxygen Stress) occurs in the chamber in a short period of time. In practice, technology is implemented at the same time ULO + ILOS for storing the best varieties of apples. Reducing the oxygen content from 21% to 5% occurs in 8-10 hours from the time of boot. The composition of the atmosphere is kept at the level of 0.9% - oxygen and 1.2% - carbon dioxide. The atmosphere is controlled by a computer control system. After 7 months of storage, it is possible to achieve the best results to preserve products in comparison with the traditional gas environment in the fruit storage.

LECA (Low Ethylene Controlled Atmosphere) is a technology where there is a decrease in ethylene level in the chamber using a catalytic ethylene converter.

To design the storage of vegetables and fruits with RGS, the following factors must be taken into account:

• ensuring the correct selection of refrigeration equipment (cooling capacity, cooling scheme, air exchange, the surface of the air coolers).
• the storage of fruits in the chambers is carried out at a temperature of from 0 to +4, as well as the relative humidity of about 90-95%.
• the tightness of the chamber should provide the greatest gas-tightness.

Technological refrigeration equipment for storage chambers with a controlled atmosphere:

• Nitric generator of RSA
• CO2 carbon dioxide adsorbing device (scrubber)
• Ethylene Converter / Cleaner
• Ventilation and protection in refrigeration chambers
• Atmospheric Control Station (SKA)
• Measuring instruments
• Optional equipment
• Sealed refrigeration chamber with bumps
• Cold System

Fruits and vegetables are very valuable food products, since it contains no replaceable complex of vitamins, enzymes and other biologically active substances necessary to maintain human health.

About 4 million tons of fruits and vegetables are produced annually in the country. However, losses in storing these products are more than 30%. As a result, in the winter-spring period, more than 50% of fruits and vegetables comes from abroad. Thus, according to these valuable foods, necessary to preserve human health, the country is experiencing a high import dependence.

The main reason for such high losses in our country is that an outdated technology of ordinary refrigeration storage is applied. It does not provide long-term conservation of products, and losses in some cases reach 40%. In addition, the preserved part of the products has low food qualities and a commodity look.

The best conservation of the quality of fruits with minimal losses can only provide storage technology in an adjustable atmosphere (RA). It should be noted that in our country for the name of this technology, the term "Adjustable Gas Wednesday" and its abbreviation -RGs is still used. The term "adjustable atmosphere" more corresponds to the essence of technology, since the same composition of gases is maintained in the chamber as in the atmosphere (N2, O2 and CO2), only their ratio is changed. Thus, the concentration of O2, in contrast to the usual atmosphere, decreases from 21 to 1-2.5%, and CO2 concentration to 1-3.5%.

The decrease in the refrigeration chamber concentration of O2 and the increase in CO2 leads to a significant slowdown in all metabolic processes occurring in the fruits. As a result, for 2-3 months, the timing of their storage is extended, losses are 2-3 times and their taste and food properties are preserved. Apples and pears can be stored until the next harvest. In countries with developed gardening (Italy, Holland, Belgium, Germany, England, USA, etc.), almost the entire commercial harvest of apples and pears intended for fresh consumption is stored in RA.

The values \u200b\u200bof the concentrations of O2 and CO2 depend on the type of product, the conditions of cultivation and other factors. Technology is constantly improving. Currently, in other countries, technology with ultra-low oxygen concentrations (ULO) is used. Abroad, and already in our country, instead of Ra, the term ULO is often used.

To implement this technology, it is necessary to have the necessary tightness and the corresponding technological equipment. It includes nitrogen generator, CO2 adsorber and automatic equipment system.

The nitrogen generator is designed for the initial decline in O2 concentration chambers, the adsorber provides a periodic removal of the CO2 released products, and the automatic control system performs a periodic measurement of CO2, O2 concentration, temperature and based on this - the inclusion of the appropriate equipment to adjust the modes.

As a nitrogen generators for this technology, membrane or adsorption gas separation plants were most widely distributed. Membrane installations are based on the use of membranes having selective permeability for O2 and N2, and adsorption - on the use of molecular sieves, selectively adsorbing one of these gases.

To remove CO2, adsorbers of various designs based on the adsorbent, absorbing this gas with regeneration by purging with clean atmospheric air.

Over the past five years, the storage technology in RA begins to apply everything in our country. This is carried out by the construction of new refrigerators with RA and by reconstructing existing refrigerators or simply industrial buildings under this technology. Each of these options has its advantages and disadvantages. Thus, in the construction of a new one, it is possible to obtain optimal in size and height of the chamber, the presence of a hall for commercial processing with an expedition and shipping gateways, to realize accommodation on the technological floor above the transport.

The use of light metal structures and thermal insulation "sandwich" - panels can significantly speed up the construction process. Modern panels have high thermal insulation properties, durable, fireproof and hygienic. Several domestic firms produce PPU panels, not inferior to foreign ones. During the construction of a refrigerator from panels, it is much easier to achieve the required tightness of the cameras, which is necessary for the implementation of storage technology in an adjustable atmosphere. As the domestic practice has shown, the refrigerator with RA by 2500-5000 t can be built for 3-4 months.

The reconstruction of an existing building under the refrigerator is cheaper, since there are no costs for zero cycle and enclosing structures. However, not in all cases it is possible to implement the optimal layout, since there are limitations in the height of the chambers.

During the reconstruction of an existing building or construction of a new storage technology in the Republic of Arch, specific requirements for fruits and vegetables to maintain high in chambers should be taken into account (88-93%). Therefore, it is very important to correct calculation and selection of refrigeration equipment with the corresponding scheme, cooling capacity, the multiple of the air exchange, the technical characteristics of the air coolers, the type of TRV, the speed of air movement, etc. Some foreign refrigeration firms, in particular Helpman and Goedhard, produce structurally optimized for long-term storage of fruits and vegetables.

Specific costs per unit of capacity during the construction of a new refrigerator depend on the project, i.e. The size and number of cameras, the presence of the hall for commercial processing, expedition, shipping gateways, technical level of the cooling system and adjustable atmosphere. This indicator can be from 40 to 70 euro scenes per 1 kg of stored products.

The cost structure in the construction of the refrigerator is also determined by the factors listed: on average, the costs of general construction work are 25-30%; on metal frame, roof and professional sheet - 15-18%; on the panel, doors - 25-30%; Non-cutting equipment - 15-18%; On the equipment of the RA - 10-12%.

In recent years, Infrostet LLC and Innovation-M LLC have implemented several projects for the construction and reconstruction of refrigerators from RA: Koshelevsky Posad LLC, Samara region (2400 tons), OPH "Central" Krasnodar Territory (800 T), LLC " Holdly "Volgograd region (1300 tons), the enterprise" Vysieto "Krasnodar Territory (2500 tons), Oak Oakovaya Tambov region (800 tons).